Induction motors typically include a stator and a rotor. The stator includes a metallic core with a plurality of coils or windings running through the core. An alternating current is passed through these coils to generate an alternating magnetic flux field. The rotor includes a plurality of coils or windings in which an alternating current is induced by the alternating magnetic flux field of the stator. The end coils or end turns of the stator are grouped together at axial ends of the stator and are laced or stitched together to prevent interference with other components of a device. The end turns may be coated with an epoxy or resin subsequent to stitching. This coating helps to reduce movement of the wires and provides an insulated barrier between the wires and other objects. Lacing in this case helps assure that the coils are tightly grouped together prior to coating.
During manufacture, each stator typically is placed on a pallet which is moved by a conveyer belt through the manufacturing facility. As part of the manufacturing process, each stator is introduced to a station at which lacing thereof occurs. Use of a stator coil lacing machine avoids many of the manual operations otherwise necessary for lacing or stitching stator end coils and thus reduces labor costs and increases productivity and quality. At the lacing station, an operator typically lifts the stator and places the stator on the lacing machine. The lacing machine generally includes a worktable having a cylindrical arbor protruding upward from a central portion of the worktable. The arbor serves to ensure proper placement of the stator on the lacing machine and aids in rotating the stator as lacing takes place. Once lacing is completed, the stator is lifted off the arbor and removed from the lacing machine to be placed back on the pallet. The larger the longitudinal length of the arbor, the more effort is required to place the stator thereon and remove the stator there from. Insertion and removal is especially difficult given the oftentimes heavy weight of the stator which includes a heavy metallic core. While use of a lacing machine provides advantages in lacing the stator coils, the need physically to move the stator from the conveyer belt pallet to the lacing machine and back again to the pallet is a tedious process which impedes the overall manufacturing process.
One characteristic of some stator coil lacing machines is that the leads of the stator coil windings must be manually held and moved during lacing of the coils of the stator. Typically, a stator includes several groups of leads for supplying power and other signals to the stator. The leads must be held and moved in order appropriately to position the leads with respect to one or more lacing needles of the stator coil lacing machine. Oftentimes the leads are manually moved and positioned such that a portion of each lead is stitched to the coil in a desired manner. This allows the leads to extend from the stator at a desired location rather than loosely falling at random positions. The desired location from which the leads extend may be caused to correspond to openings in the stator housing which provide the leads with access outside the housing. Thus, one or both of the hands of the operator of a stator coil lacing machine is/are often preoccupied in positioning the leads during lacing of the coils of the stator. This has the disadvantages of preventing the operator from performing other tasks during stator coil lacing and thus lowers his or her productivity. In addition, an operator needs to be cautious so as to not carelessly come in contact with moving components of the stator coil lacing machine such as the lacing needles.
Therefore, there is a need in the art to reduce the amount of manual intervention needed during lacing of stator coil windings so as to mitigate the aforementioned shortfalls of conventional methods and devices.